Urinary Bisphenol A (BPA) Concentrations among Workers in Industries that Manufacture and Use BPA in the USA

Background: Bisphenol A (BPA) toxicity and exposure risk to humans has been the subject of considerable scientific debate; however, published occupational exposure data for BPA are limited. Methods: In 2013-2014, 77 workers at six US companies making BPA, BPA-based resins, or BPA-filled wax provided seven urine samples over two consecutive work days (151 worker-days, 525 samples). Participant information included industry, job, tasks, personal protective equipment used, hygiene behaviors, and canned food/beverage consumption. Total (free plus conjugated) BPA, quantified in urine by mass spectrometry, was detected in all samples. Results: The geometric mean (GM) creatinine-adjusted total BPA (total BPA(CR)) concentration was 88.0 mu g g(-1) (range 0.78-18 900 mu g g(-1)), similar to 70 times higher than in US adults in 2013-2014 (1.27 mu g g(-1)). GM total BPA(CR) increased during Day 1 (26.6-127 mu g g(-1)), decreased by pre-shift Day 2 (84.4 mu g g(-1)) then increased during Day 2 to 178 mu g g(-1). By industry, baseline and post-baseline total BPA(CR) was highest in BPA-filled wax manufacturing/reclaim (GM = 111 mu g g(-1)) and lowest in phenolic resin manufacturing (GM = 6.56 mu g g(-1)). By job, total BPA(CR) was highest at baseline in maintenance workers (GM = 157 mu g g(-1)) and post-baseline in those working with molten BPA-filled wax (GM = 441 mu g g-1). Workers in the job of flaking a BPA-based resin had the lowest concentrations at baseline (GM = 4.81 mu g g(-1)) and post-baseline (GM = 23.2 mu g g(-1)). In multiple regression models, at baseline, industry significantly predicted increased total BPA(CR) (P = 0.0248); post-baseline, handling BPA containers (P = 0.0035), taking = 3 process/bulk samples with BPA (P = 0.0002) and wearing a Tyvek (R) coverall (P = 0.0042) significantly predicted increased total BPA(CR) (after adjusting for total BPA(CR) at baseline, time point, and body mass index). Conclusion: Several work-related factors, including industry, job, and certain tasks performed, were associated with increased urinary total BPA(CR) concentrations in this group of manufacturing workers. The potential for BPA-related health effects among these workers is unknown.